This invention relates to a method of screening for medically relevant fungi. In recent years there has been an increase in the awareness of the importance of a healthy indoor environment. A central dynamic affecting the quality of the indoor environment is the control and removal of biological contaminants, mainly the filamentous fungi (mold). Estimates of fungal contamination of homes in North America indicate that up to 40% contain mold growth, while in other parts of the world such as Northern Europe the proportion of fungal contaminated homes ranges between 20-40%. Fungal contaminants that can inundate the indoor environment include microbial volatile organic compounds (MVOC), allergenic proteins, and in some cases mycotoxins.
Adverse health effects that have been attributed to the filamentous fungi include itchy eyes, stuffy nose, fatigue, headache, and in severe cases idiopathic pulmonary hemosiderosis (IPH) in infants resulting in death. The term sick building syndrome accurately reflects the potential that molds can have on the built environment. Currently, only a small percentage of these fungal contaminants have been implicated in adverse health effects. However, with the increased interest and research aimed at these organisms it is probable that the list of organisms that induce ill health will be expanded.
Fungal organisms have historically been identified based on morphological characteristics, both macroscopic and microscopic. Examination of the traits and distinctions of the colonies, and morphological characteristics such as conidial size, texture, shape, and structure are all commonly used methods of identification. Because these methods may require up to two weeks for an identification to be made, these prior art methods are time consuming and highly inaccurate. It is extremely difficult to distinguish between organisms that are similar morphologically. Additionally, not all of the organisms in a sample will be culturable. This inevitably leads to misidentification and understatement of the organisms that constitute the microbial community. Due to these concerns it is imperative that new methods of fungal identification be developed that are rapid, specific, easy to perform, and cost effective. Because of these concerns, there is need for molecular biology techniques that circumvent many of the problems related to morphological identification. Techniques that have proven successful include quantitative Polymerase Chain Reaction (qPCR), restriction fragment length polymorphism (RFLP) analysis, random amplified polymorphic DNA (RAPD) analysis, and image analysis. Each of these methods has been used successfully to identify and/or quantify fungal organisms from a number of different environmental samples. These methods enable rapid, sensitive, and specific identification of fungal organisms, However, in most cases they are only being used to identify single organisms from complex environmental samples. However, fungal organisms found in the environment are rarely if ever encountered singly. A more practical approach is the identification of numerous organisms from a single environmental sample. Identification of multiple fungal species in a single PCR-based reaction would save time and money, while maintaining high specificity and accuracy.